The International Court of Justice (ICJ) delivers its Chagos Islands Advisory Opinion, and UK loses badly

The ICJ has ruled that Britain acted illegally when it imposed territorial controls on the Chagos Islands without the consent of Mauritius. The ruling may hinder US operations in Diego Garcia, where it holds an airbase on lease from the British.

The UN Court ruling also accuses Britain of ignoring the rights of Mauritius, which claims the islands as its own. Mauritius also claims that declaring the remote Indian Ocean archipelago a marine protected area (MPA) has damaged its fishing industry in surrounding waters.

The British Labour government at the time of the MPA declaration (April 2010) is also found to have forced through the MPA measure to strengthen its hand in the impending election.

Marko Milanovic discusses the outcome in this blog from the European Journal of International Law blog—HLRN.

Earlier this afternoon the ICJ delivered its Chagos advisory opinion. Briefly, the Court found that the separation of the Chagos archipelago from the British colony of Mauritius was contrary to the right to self-determination and that accordingly the decolonization of Mauritius was not completed in conformity with international law. As a consequence, the Court found that the UK’s continuing administration of the archipelago, which includes the largest US naval base in the Indian Ocean, Diego Garcia, is a continuing internationally wrongful act, which the UK was under an obligation to cease as soon as possible. The Court was almost unanimous – its decision not to exercise discretion and decline giving an opinion was made by 12 votes to 1, while its findings on the merits were made by 13 votes to 1 (Judge Donoghue dissenting). The AO and the various separate opinions is available here.

Here are some key takeaways:

First, on the issue of the exercise of discretion/propriety to give an opinion, the key issue here was whether, in answering the questions posed by the General Assembly the Court would be effectively deciding on a bilateral dispute between states over territorial sovereignty, which one of them (the UK) did not consent to (for more background on this issue see Dapo’s earlier post here). Here Judge Tomka joined Judge Donoghue in thinking that the Court should have declined giving an opinion, consistently with his prior position in the Kosovo AO. The Court effectively gets around this problem by labeling the advisory proceedings as being about decolonization, an issue in which the UNGA has a longstanding interest, rather than about sovereignty.

Technically, the Court is right, except that its finding on the illegality of the decolonization process inevitably impacts on the British sovereignty over Chagos; either the UK really has no sovereignty over the islands at all, or it is the sovereign but is obliged to relinquish that sovereignty to Mauritius as soon as practicable. The situation is comparable to some extent to the South China Sea arbitration, in which the arbitral tribunal technically avoids issues of sovereignty but by deciding on the nature of certain maritime features, and their (in)ability to project maritime areas, it effectively completely demolishes China’s claim to these areas.

Second, this shows just how important questions of characterization and framing can be. This is particularly true of the formulation of the question, which as I argued before was VERY clever on the part of Mauritius (as later adopted by the GA). Readers will recall that the question is in two parts:

(a) “Was the process of decolonization of Mauritius lawfully completed when Mauritius was granted independence in 1968, following the separation of the Chagos Archipelago from Mauritius and having regard to international law, including obligations reflected in General Assembly resolutions 1514 (XV) of 14 December 1960, 2066 (XX) of 16 December 1965, 2232 (XXI) of 20 December 1966 and 2357 (XXII) of 19 December 1967?”;

(b) “What are the consequences under international law, including obligations reflected in the above-mentioned resolutions, arising from the continued administration by the United Kingdom of Great Britain and Northern Ireland of the Chagos Archipelago, including with respect to the inability of Mauritius to implement a program for the resettlement on the Chagos Archipelago of its nationals, in particular those of Chagossian origin?”

Again, by avoiding the use of the term “sovereignty,” Mauritius and the GA defused the likelihood of the Court dismissing the case as involving a bilateral dispute, as does the use of the term ‘continued administration’ in part (b). When asked to reformulate or narrow down the question, the Court expressly refused to do so, and indeed said that it sees no reason to interpret it restrictively (paras. 136-137). In her dissent, Judge Donoghue openly floats the option of the Court narrowing down the question and providing a limited answer on the merits, something she would have been happy with – in fact she expresses no disagreement of principle with the Court’s findings on the merits.

Third, when it comes to self-determination, the key question for the Court to decide was whether it was already a rule of customary law by 1968, when Mauritius was granted independence – see this recent post by Orfeas and Sarah for more background. This is an admittedly a very difficult question – at what point in time exactly does a rule of customary IL actually crystallize? And the Court completely fudges it. It simply relies on a series of GA resolutions, to which it expressly ascribes a normative character (para. 153), and just asserts that self-determination was already customary at the relevant time. No state practice, no opinio juris, no nothing – just good plain assertion, as the Court is so often wont to do.

Fourth, the Court’s conclusion that Mauritius did not genuinely consent to the separation of Chagos is quite rushed (para. 172), and effectively turns around the application of a standard of heightened scrutiny in situations when consent is expressed by a subordinate administration. The Court seems to be saying here (by implication) that only something like a referendum could have constituted a free expression of the will of the people. The Court thus then logically concludes that the answer to question (a) was that the decolonization of Mauritius was not lawfully completed.

Fifth, proceeding to question (b), the Court effectively treats the consequence of (a) as a matter of state responsibility, holding (para. 177) that ‘the United Kingdom’s continued administration of the Chagos Archipelago constitutes a wrongful act entailing the international responsibility of that State’ which is of a continuing character. Then, para 178: ‘Accordingly, the United Kingdom is under an obligation to bring an end to its administration of the Chagos Archipelago as rapidly as possible, thereby enabling Mauritius to complete the decolonization of its territory in a manner consistent with the right of peoples to self-determination.’

This is obviously where the UK just totally lost the case. There’s no silver lining here. The Court could have chosen to fudge this somewhat, but it went full in (and again, did so virtually unanimously, even if some of the judges were not entirely comfortable with the language of state responsibility).

Finally, the Court noted that all UN member states must cooperate to finalize the decolonization of Mauritius (para. 180), since self-determination is an obligation erga omnes, and that the GA must ensure the protection of the human rights of the expelled Chagossians (para. 181). The ‘all states’ obviously includes the United States re Diego Garcia and all.

It is very interesting just how brief the Court’s answer to question (b) is – the big blow to the UK is of course the framing of its presence in Chagos as a continuing wrongful act. Otherwise, however, the Court wanted to be as non-prescriptive as possible. Even on the matter of the return of the Chagossians it says more through silence than words.

It remains to be seen, of course, how the UK government will react to all this. Things are not going all that well in Whitehall anyway, and there’s now not only Brexit, but also Chexit, to worry about.